One type of paint bake oven which is conventionally used to bake painted vehicle bodies includes an elongated housing of a rectangular cross-section to which heated gas is supplied to provide baking of painted vehicle bodies upon conveyance through the housing. This type of oven conventionally includes a pair of gas supply ducts respectively extending along the upper lateral corners of the housing and having outlets for directing the heated gas downwardly against the floor of the housing to provide gas deflection back up toward the conveyed vehicle bodies. A damper conventionally extends between the pair of supply ducts and is adjustable to control the flow of gas upwardly to an outlet duct through which the gas is returned to a heater prior to flow back to the supply ducts in a recirculating fashion.
Vehicle body paint bake ovens of the type described above are conventionally fabricated at the factory site where the oven is to be used and, as such, considerable erection time and costs are normally involved with such ovens. Also, the fabrication of the oven at the factory site often results in gas leaks that reduce the efficiency of the oven and emit contaminated gas to the factory atmosphere. Deflection of the heated gas upwardly from the floor of the oven housing also creates a turbulence that picks up dust and dirt particles which can adhere to the wet paint on the vehicle bodies prior to drying and thereby produce defects when the paint finally dries. To overcome this problem, radiant heaters have been utilized in the oven at its upstream end just downstream from where the vehicle bodies are spray painted. Radiant heating of the vehicle bodies thus initially dries the paint without the use of circulating heated gas that can carry dust or dirt particles to the wet paint.
Further problems arise from the prior art ovens being rectangular. The ovens are made from insulated panels connected at joints and are supported from an I-beam frame. Condensation of paint fumes saturate the panels at the joints. This condition increases heat losses and creates a potential fire hazard.